5: Expirimental Research

Question 1

Expiriment

Answer 1

A type of study designed specifically to answer the question of whether there is a causal relationship between two variables.
- researchers manipulate, or systematically vary, the level of the independent variable (or, conditions)
- researcher exerts control over, or minimizes the variability in, variables other than the independent and dependent variable (extraneous variables)

Question 2

Conditions

Answer 2

The different levels of the independent variable to which participants are assigned.

Question 3

Control

Answer 3

Holding extraneous variables constant in order to separate the effect of the independent variable from the effect of the extraneous variables.

Question 4

Manipulate

Answer 4

Changing the level, or condition, of the independent variable systematically so that different groups of participants are exposed to different levels of that variable, or the same group of participants is exposed to different levels at different times.

Question 5

Single Factor Two-Level Design

Answer 5

An experiment design involving a single independent variable with two conditions.

Question 6

Single Factor Multi-Level Design

Answer 6

When an experiment has one independent variable that is manipulated to produce more than two conditions.

Question 7

Confounding Variable

Answer 7

An extraneous variable that varies systematically with the independent variable, and thus confuses the effect of the independent variable with the effect of the extraneous one.
- can be limited by holding extraneous variables constant

Question 8

Treatment

Answer 8

Any intervention meant to change people’s behavior for the better.

Question 9

Treatment Condition

Answer 9

The condition in which participants receive the treatment.

Question 10

Control Condition

Answer 10

The condition in which participants do not receive the treatment.

Question 11

Randomized Clinical Trial

Answer 11

An experiment that researches the effectiveness of psychotherapies and medical treatments.

Question 12

No-Treatment Control Condition

Answer 12

The condition in which participants receive no treatment whatsoever.

Question 13

Placebo

Answer 13

A simulated treatment that lacks any active ingredient or element that is hypothesized to make the treatment effective, but is otherwise identical to the treatment.

Question 14

Placebo Effect

Answer 14

An effect that is due to the placebo rather than the treatment.

Question 15

Waitlist Control Condition

Answer 15

Condition in which participants are told that they will receive the treatment but must wait until the participants in the treatment condition have already received it.
- potential solution to the placebo issue

Question 16

Between-Subjects Expiriment

Answer 16

An experiment in which each participant is tested in only one condition.

advantages:
- being conceptually simpler and requiring less testing time per participant
- avoid carryover effects without the need for counterbalancing

Question 17

Within-Subjects Expiriment

Answer 17

An experiment in which each participant is tested under all conditions.

advantages:
- controlling extraneous participant variables, which generally reduces noise in the data and makes it easier to detect any effect of the independent variable upon the dependent variable
- require fewer participants than between-subjects experiments to detect an effect of the same size

Question 18

Random Assignment

Answer 18

Means using a random process to decide which participants are tested in which conditions.

Question 19

Block Randomization

Answer 19

All the conditions occur once in the sequence before any of them is repeated.

Question 20

Matched-Groups Design

Answer 20

An experiment design in which the participants in the various conditions are matched on the dependent variable or on some extraneous variable(s) prior the manipulation of the independent variable.

Question 21

Order Effect

Answer 21

An effect that occurs when participants’ responses in the various conditions are affected by the order of conditions to which they were exposed
- primary disadvantage of within-subjects designs

Question 22

Carryover Effect

Answer 22

An effect of being tested in one condition on participants’ behavior in later conditions.
- includes practice effect, fatigue effect

Question 23

Practice Effect

Answer 23

An effect where participants perform a task better in later conditions because they have had a chance to practice it.

Question 24

Fatigue Effect

Answer 24

An effect where participants perform a task worse in later conditions because they become tired or bored.

Question 25

Context Effect (or Contrast Effect)

Answer 25

Unintended influences on respondents’ answers because they are not related to the content of the item but to the context in which the item appears.
- also includes effect of people guessing the hypothesis (demand characteristic)

Question 26

Counterbalancing

Answer 26

Varying the order of the conditions in which participants are tested, to help solve the problem of order effects in within-subjects experiments.
- controls the order of conditions so that it is no longer a confounding variable (any overall difference in the dependent variable between the conditions cannot have been caused by the order of conditions)
- if there are carryover effects, it makes it possible to detect them (one can analyze the data separately for each order to see whether it had an effect)

Question 27

Complete Counterbalancing

Answer 27

A method in which an equal number of participants complete each possible order of conditions.
-ie. possible orders of ABC: 1/6 complete each ABC, BCA, CAB, ACB, BAC, CBA

Question 28

Complete Counterbalancing

Answer 28

A method in which an equal number of participants complete each possible order of conditions.
-ie. possible orders of ABC: 1/6 complete each ABC, BCA, CAB, ACB, BAC, CBA (can use latin square)

Question 29

Random Counterbalancing

Answer 29

A method in which the order of the conditions is randomly determined for each participant.

Question 30

Internal Validity

Answer 30

Refers to the degree to which we can confidently infer a causal relationship between variables.

Question 31

External Validity

Answer 31

Refers to the degree to which we can generalize the findings to other circumstances or settings, like the real-world environment.

Question 32

Mundane Realism

Answer 32

When the participants and the situation studied are similar to those that the researchers want to generalize to and participants encounter every day.
- high external validity

Question 33

Psychological Realism

Answer 33

Where the same mental process is used in both the laboratory and in the real world.
- can have low external validity

Question 34

Construct Validity

Answer 34

One of the “big four” validities, whereby the research question is clearly operationalized by the study’s methods.

Question 35

Operationalization

Answer 35

The specification of exactly how the research question will be studied in the experiment design.

Question 36

Subject Pool

Answer 36

An established group of people who have agreed to be contacted about participating in research studies.
-ie. university psych students

Question 37

Experimenter Expectancy Effect

Answer 37

When the experimenter’s expectations about how participants “should” behave in the experiment affect how the participants behave.

Question 38

DOuble-Blind Study

Answer 38

A method to reduce experimenter bias, where neither the participant nor the experimenter is knowledgeable about the condition to which the participant is assigned.

Question 39

Manipulation Check

Answer 39

Verifying the experimental manipulation worked by using a different measure of the construct the researcher is trying to manipulate.
- if proves that manipulation did not work, that means results are valid to the construct measured (including if they are null)
- better to conduct in a pilot test ot avoid using an invalid manipulation for actual research

Question 40

Pilot Test

Answer 40

Is a small-scale study conducted to make sure that a new procedure works as planned.